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10bolt front diff tech

backcountryislife

Well-Known Member
Messages
858
Location
Dumont, CO
So, overall this is what I have in my mind....and I know my day has passed but I still think that you all can benefit from how we did the IFS upgrade in my H3.

This was one of the inspirations for what we ended up doing. This being one extreme and digger being the other.

ce-4305a.jpg


Currie will also tube either side and add the bearing retainer and seals. But honestly the possibilities are endless as far as application goes.

wow, that thing is mean... for $2k it better be, but that's a pretty cool setup if someone could afford it.


What made you go D44 instead of one of those?
 

bebe

Moderator
Messages
1,375
Location
Dayton, NV
wow, that thing is mean... for $2k it better be, but that's a pretty cool setup if someone could afford it.


What made you go D44 instead of one of those?

Well for 1, you can do essentially the same thing with any straight axle housing of any size, and for 2, I wasn't building a trophy truck, but I did come awfully close to buying one. Very close.

$1,800 for this or $950 for an experiment.....don't get me wrong, I think mine was a junk yard build with the exception on the a-arms and drop cradle. It's the overall principle and design of the Currie (Dutchman and RuffStuff have them too) if it's strong enough for a trophy truck, it will hold up the the trails we frequent.
 
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06 H3

a.k.a. "The Jackal"
Messages
9,492
Location
Meridian, ID
Now that's a nice piece there bebe! 1800 for just the housing and start adding up more price for the tubes, retainers etc? It's badass. If I do that I should go for more flex then also but that's a different topic for a different day. Lol
 

MaxPF

AGNTSA
Messages
1,394
Location
The dark side of the globe
Thanks for chiming in max! I'm more interested in keeping the ifs for now with the 10b centersection. I may pick up an axle and start investigating myself. As for width, I'm trying to keep it to a minimum so I don't need to make new longer control arms and such.

Good luck with that. The AAM front in the H3's are pretty compact. I don't see any way of building a 10b front that will be anywhere near that narrow.

With a 10b rear chopping it making custom flanges and c clips my main confusion is axle seals. Is there any main things Id have to do? Is it just a bearing retainer and seal? I'm kinda new to the seal and bearing deal.

Chopping up my own 10b is fine and even setting up gears. It's making sure axle plunge is correct, setting up seals and mounting (which I have a few ideas)

Biggest thing is making sure there is minimal radial movement inside the seal. This means the shaft needs to be supported by a bearing relatively close to the seal. Using the side gear to support the other end is usually adequate.

In any normal SA application the wide bearing spacing of the 10-bolt is a plus. But its a handicap for what we're trying to do...very little room under the H3, and by the time you add a bearing, seal and flange to the IFS...its gonna get wide (maybe too wide). Hopefully the shorter 1500 half-shafts will allow you to keep it out of the oil pan.

Unfortunately, the overall dimensions of a D44 housing are basically the same. I don't think you will get either one to fit into the space of the AAM 7, width-wise.

While the 8.5 and 8.6 share the same ring-gears...I noticed the late-model 8.6 housing under the rear of the H3 is clearly a cleaner, beefier casting. Perhaps this is due to modern CNC manufacturing process rather than 70's slide-rule technology?...I'm not sure.

It's mainly modern casting technology. In the past, molds were simple sand casting molds, which were prone to core shift. Thus, margins in cross sections had to be included to assure adequate casting thickness in all areas regardless of core shift. Modern parts are done using more advanced sand casting methods that can maintain much higher accuracy. This allows near "net-shape" parts and very close control of cross sectional thicknesses. This allows the manufacturer to make the housing lighter, with ribbing in needed areas for structural rigidity. Thus, the newer castings are certainly "cleaner", but not necessarily stronger.

But it makes sense to me to use the latest, most advanced parts you can find. I would think that after 35 years...the H3's 8.6 probably has quite a bit of improvements built into it that might not be obvious to the naked eye.

Only real improvement is the larger carrier bearings, and maybe the extra structural ribs between the center and the tube bosses. As I mentioned earlier, they don't seem to be any more rugged than their earlier counterparts. They are adequate for their purpose in the H3 (up to 35" tires), but GM really should be using the 9.5" axle in their current 1/2 ton trucks.

The pumpkin is cast without the leaf-spring perch, which may actually benefit somebody trying chop and add a bearing/seal to it. At first, I thought having the extra meat of the perch might help, and you could use it to support a bearing. But after cutting apart a front 10-bolt housing and looking closely at it...I think the smaller RWD pumpkin might allow for easier chopping. Try to use the tube if possible, rather than milling deep into the casting. I don't see a problem running this axle in the front position. As someone else pointed out...all the low-pinion stuff runs on the coast-side of the teeth anyway, and they've been doing this for 50 years. I have no idea what effect this would have on a used gear-set (that had been previously ran in the other direction)...but, its worth a try.

In theory, the coast side is weaker. In practice, stock shafts and joints (and usually stock size alloy shafts) always fail first. The only time the R&P starts to become an issue is when aftermarket large spline alloy shafts are used with big tires, i.e. 37 spline chromoly shafts in D60's running 42"+ tires. Then you start to see R&P failures. Whether a high pinion would do better in this case is unknown, although measurements have shown that there is considerably more carrier deflection in a LP front vs a HP front. The typical fix for this is the Jana 76 mod, where a D70 carrier, ring, and pinion are installed in the D60 housing. The D70 has a 10.5" ring gear vs the 9.75" gear in the 60. Thus far, guys who have had repeated D60 R&P failures have not had failures with the 76 mod, AFAIK. What's really cool is that there is also a Jana 54 mod, where the 9" Dana 50 R&P is installed in the D44 housing. You can read about the Jana 76 and Jana 54 mods here: :link: It should be noted that these mods are only needed for someone who is routinely reaching the limit of their D60 or D44 R&P. In other words, 99.99% of us will never need this.

I wouldn't complain about $950 for one of these. Remember, you're saving a grand by having the E-locker and matching gears already installed in it. Not only that but, all of your bearings, seals, and set-up is already done for you. You can simply un-load housing...do the chop...clean it up...and put everything back it the same position. I say this only because its a "prototype", and everything at this point is experimental. You can always do a re-gear to both axles after testing your IFS with stock gears.

I dunno... $950 sounds kinda high to me. I'm asking barely more than half that for a 9.5" axle with an E-Locker, and I only paid $300 for a 10.5" full floater with factory disk brakes and a factory G80 locker... I guess it's whatever the market will bear.

Just so you guys know - re-gearing the rear end in these is a Pita - do it once. If you remember, we had to do some dental work to get the cross pin in on the 5:13's. That will add to the cost. It's tedious and time consuming. (For those who won't be doing it themselves).

10b axles aren't that bad. Regearing Dana axles sucks way worse because the shims are located behind the press-fit carrier bearings. Setup bearings significantly relieve the pain in this case.

The housing we used, by luck was a HD D44. We looked at the HP D44 TTB and it would have been perfect, but we didn't want to mess with tubing it.

The front is also a 35 spline ARB, with Cry-o treated star splined chomoly stub shafts.

The HD D44 is a good piece for a front SAS as well since it has the heavy 1/2" wall tubes. Only thing better is a 60.


I didn't think swapping the rear gears was too tough. Grinding the tooth took me all of 10 minutes with a die-grinder, once I found out that was the fix (thanks Bebe). A bigger hassle was simply getting the axle shafts out! The ABS rings are glued onto the axle shafts about 6" from the ends, and they don't pull-out like normal C-clip shafts. I recommend prying them out from inside the window of the carrier...and not from the flange end. I destroyed both of my axle seals with a pry bar. No biggy...my GM dealer had the seals in stock but, in retrospect...if you pry at the C-clip ends, you won't mangle the seals out at the ends of the tubes.

The first time I worked on an H3 rear axle, I was puzzled that the shafts didn't simply slide out when the c-clips were removed (and pushing the shafts in far enough to get the clips off was a PITA as well). Wasn't 'till later that I figured out why. Anyway, yes, using a pry bar on the end of the shaft inside the carrier is the best way to get them out.

Once you get the shafts out...you get to wrestle around with the actuator coil on the Eaton locker. You have to sort of disconnect it and leave it in place, so you can pull the carrier out. Its not too tough...but a second set of fingers helps. After that...its pretty much a normal gear-swap.

Not sure what you mean by "wrestle around with the actuator coil". You use a small pin to release the terminal ends from the plastic connector, then push the rubber plug/feed-thru back into the housing. After that, no problems. To date, I have done 5 E-locker installs (2 8.5" 10b front axles, 1 8.6" 10b axle (Alrock's H3), and 2 9.5" 14b axles), and I have R&Red and rebuilt two more E-lockers (both in H3's). Once you get the hang of it, they are easy.
 
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atvspeed4

Well-Known Member
Messages
1,209
Location
massachusetts
S.O.B that was an awful day fighting with the damn ten bolt! We went to do the mounting fab work today and well that sucked. I can define a few things that we have all been talking about since 2006:

#1 a GM 2500 CV will fit perfectly in the knuckle BUT.... the boot will rub hard against the lower control arm and will not clear the swaybar link. Even if you ran no swaybar the boot will be destroyed by rubbing the control arm. There is no way around this.

#2 The 8.5" ten bolt will fit but requires the diff to be dropped and custom mounts to be made.

#3 You WILL need to make a custom diff crossmember. The stock one is not even close.

#4 You will need to make a custom skid plate. I dont care if its a hi-pinion diff or a low pinion you are going from a 7.2" ring gear to a 8.5" and that makes the diff taller. About 1.5" taller. You shouldnt lose ground clearance though.

#5 You will need to cut the 8.5" cast housing down all the way to the gasket surface.

#6 You will need some $$$ custom flanges made and I mean custom as in turning down a 6" 4340 chromoly round or having custom forged blanks made. You cannot use ordinary alloy axle shaft blanks because they have a "cone" taper on the back side of the flange face that increases the length too much.


So it looks like I will have to run GM 1500 cvs because the boots will be destroyed on 2500s due to severe rubbing on the control arm. I'll also have to make some pricey flanges.
 

atvspeed4

Well-Known Member
Messages
1,209
Location
massachusetts
Every thing. Cv joint size, boot size, center shaft size, strength. They are the same length but the 2500 weighs 3 lbs more. It's friggin massive! From a rough measurement the 1500 is bigger than stock but should still fit.
 

4speedfunk

Well-Known Member
Messages
4,244
Location
Tardville
Biggest difference?....H3 half-shafts "plug-in" to the AAM-7. 1500 and 2500 shafts "bolt-in" to flanges.

I feel that any of these three choices is perfectly acceptable. It makes sense to go with the biggest one you can fit in there but, at some point you have to ask yourself: "Are the mods required to fit it, worth the extra strength?". In this case...probably not. I would run the 1500 shafts, if it would save me from custom-making lower A-arms. Half-shafts will ALWAYS require extra attention, and periodic replacement...so using something as common as the GM full-size is the way to go. It also opens up choices for aftermarket shafts...something you'll loose if you go with custom shafts. Considering the use you're building for...being able to walk-into any NAPA or AutoZone and grab a new half-shaft for $90, is a HUGE advantage.

Even though the 1500 shafts might be the same strength as stock ones...the bolt-in design is certainly better. I never liked the stock plug-in design, and it is very hard to get more than 30K miles out of a stock H3 axle seal. I think captured axles and flanges would make for a longer seal life at the diff. Bolt-in style half-shafts also give you the option to completely remove a broken one on the trail and drive back to pavement, without loosing oil.
 
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PCH2

Well-Known Member
Messages
222
Location
Park City, UT
Ok, reading through all this has made my head spin. You guys are like Jedi H3 Gurus, you guys amaze me. If it aint sticks, bricks and mortar, Im Lost. Ok here is the question. Mine, 2010 H3 Lux Base. Installed rear ARB e-locker. Wanting to get the best performance, on the trail, we are looking to add locker to front. Local Six States will not install because carrier is aluminum. I understand the failure rate in a aluminum carrier, but there has to be a solution. What I came up with is getting the carrier from GM that lists the part as having a locker. $400.00 +- for the part, having the ARB locker installed (1200.00 local) with stock internal components from existing differential, OR GM has complete axle and diff assembly for $1800.00 +-. Does anyone have any suggestions for trying to achieve what we are trying to do? Oh yeah, trying to do this in three weeks before Moab 2013!
 

4speedfunk

Well-Known Member
Messages
4,244
Location
Tardville
You could also grab a used front axle from a salvage 2009-2010 Adv. Pak. This would be the cast iron version, and it would also have a pre-installed locker. Probably around $1000 if you can find one.
 

PCH2

Well-Known Member
Messages
222
Location
Park City, UT
You could also grab a used front axle from a salvage 2009-2010 Adv. Pak. This would be the cast iron version, and it would also have a pre-installed locker. Probably around $1000 if you can find one.

Thanks, I will call around tomorrow for salvaged parts, only problem here in Utah, not many H3 adv parts.
 

PCH2

Well-Known Member
Messages
222
Location
Park City, UT
GM parts direct has that cast iron housing and e locker for about 1200. Not sure what shipping would be.

It is out of stock. No one shows one anywhere, also checked nationwide for the assembly through salvage yards, nothing. Next question, part number 25831502 is cast iron carrier from h3 adv 3.7 manual. Can I swap my guts to this carrier and add e-locker to that? That way I am just scraping my aluminum carrier. I now know this ain't gonna happen before Moab.
 

bebe

Moderator
Messages
1,375
Location
Dayton, NV
It is out of stock. No one shows one anywhere, also checked nationwide for the assembly through salvage yards, nothing. Next question, part number 25831502 is cast iron carrier from h3 adv 3.7 manual. Can I swap my guts to this carrier and add e-locker to that? That way I am just scraping my aluminum carrier. I now know this ain't gonna happen before Moab.

Yes you can do that.

Yes you can, but we should note that you will need extra parts, contact a place like Randy.s R&P or West Coast Differentials (Jay or John) and ask them. You won't have to research anything, it's what these guys get paid for...to make your life easier. :)

Ask Jay or John to call AAM (American Axle) and have them locate one. No one that I know of shows them as in stock. You have to get out there and find them.

Edit: Page 34 on WCD shows cases
http://differentials.com/wp-content/uploads/2011/09/2012-WCD-Catalog.pdf

They can also get ARB's and do all the set up for you.
 
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atvspeed4

Well-Known Member
Messages
1,209
Location
massachusetts
Time for a small update:

It looks like this project will not allow the use of off the shelf 1500 shafts but not 100% yet. We are going to try and take another 0.5" off the diff. The problem is that the ujoint will make contact with the oil pan. The diff has had the tube cut all the way down to the cover gasket surface and we are using the shortest 1500 shafts they made. It looks like the only way this would fit would be with a rancho lift unfortunately.
 

06 H3

a.k.a. "The Jackal"
Messages
9,492
Location
Meridian, ID
Seeing the diff is all the way to the gasket surface do u feel like a substantial amount of strength has been given up
 

Bigunit

Hammer Down!
Staff member
Messages
6,561
Location
Arizona
I applaud and thank you for the effort, it's fabricators like you who make this a fun and interesting hobby for me but this doesn't sound like a simple, practical or cheap DIY mod for someone like me. Just my humble opinion. By the time I'm ready to consider and spend $$$ on these mods, I'm afraid that I'll be buying a new trail rig. But for everyone else, keep up the great work.

Sent from my DROID RAZR using Tapataint
 

06 H3

a.k.a. "The Jackal"
Messages
9,492
Location
Meridian, ID
I agree with BU. I wish I could do the stuff you guys do. Even if I had the tools id still be doing guess work. Hats off to you
 
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